The present invention relates generally to dispenser assemblies for receptacles such as fragrance or personal care bottles, and in particular, to an improved collar for use therewith that significantly reduces the likelihood that the dispenser assembly will inadvertently or undesirably become decoupled from the receptacle, without sacrificing the ease of which the collar can be initially positioned thereon. That is, the present invention is directed to an improved dispenser assembly that maximizes the xe2x80x9coff-to-onxe2x80x9d force of application and removal forces for the collar. An improved method of assembling the dispensing assembly on the receptacle is also provided.
Generally speaking, prior art fragrance and personal care pumps consist of a pump module, a manual actuator for operating the pump, a ferrule that contains the module and crimps onto the receptacle (i.e. glass or plastic container), a gasket that seals the ferrule to the top of the receptacle""s neck and a decorative collar. A cap may also be provided over the collar either in a slip-fit or a snap-fit arrangement.
Typically, the pump is retained on the bottle by one of two methods:
(a) the lower edge of the ferrule, typically comprised of aluminum, is collapsed inwardly under the neck of the receptacle by a crimping tool. After mounting, the collar is pushed over the ferrule as a separate operation; or
(b) a ferrule, made of either plastic or metal, has its multiple legs folded under the neck of the receptacle by sliding the collar down the ferrule. The collar is partially preassembled to the ferrule at the pump manufacturer""s plant and the assembly is then mounted on the bottle at the customer""s plant in one operation.
In either case, the collar can be metal or plastic. Usually, retention of a plastic collar on the ferrule is not a major concern because designs incorporate snap fits or heavy press fits that do not compromise the outer aesthetics of the collar. However, metal collars are usually fabricated in aluminum and then anodized to produce a lustrous surface. In order to accommodate physical tolerances in the ferrule and collar diameters, the internal surface of the collar may contain multiple elongated vertical ribs (see FIGS. 1 and 1A) that project outwardly several thousandths of an inch off the inner surface thereof. When the collar is pushed over the ferrule with a heavy press fit, the collar slightly distorts, or xe2x80x9cbreathes,xe2x80x9d into a polygon, giving it a resiliency that deals with the tolerances. Another attribute of the ribs is to concentrate the xe2x80x9choopxe2x80x9d stress at multiple points, causing the ribs to dig into the ferrule and thus increasing the resistance to removal.
However, finding the optimal parameters that provide the best seal of the pump to the receptacle is difficult and heretofore has been elusive. For example, although the press fit over the ferrule must be large enough to assure that the collar cannot be accidentally pulled off the ferrule, it must be low enough to avoid damaging the outer surface of the collar. That is, the anodized surface of the collar is typically a very thin film of aluminum oxide that contains a colorant dye. When stressed in tension, the oxide film can crack, creating a diffraction grating that produces a rainbow effect, which detracts from the aesthetics. As a result, the rib locations become evident on the outer surface of the collar, a condition known as xe2x80x9ccrazingxe2x80x9d.
Similarly, while the press fit must be high enough to compress the gasket sufficiently to assure a seal to the bottle neck so as to avoid leaking, the press fit should not be so high as to over-compress the gasket, causing it to extrude out from under the ferrule, or creating such large forces that the bottle collapses or breaks.
Accordingly, it can be seen that improvements in the art are still desired. Specifically, it is desired to improve the state of the art collars to be able to increase the needed force to remove the collars while simultaneously not requiring so much force in initially applying the collar that crazing, bottle leaking or breaking occurs.
One such proposal that has been suggested is to provide spiraling ribs in the inner surface of the collar. One exemplary construction that appears to utilize spiral ribs is described in U.S. Pat. No. 5,799,810. However, it is believed that the descriptions and the resultant product therein are less than satisfactory and that still further improvements are achievable. Specifically, it is believed that the spiral ribs in this ""810 patent are not provided to hold the collar on, but rather, to permit the collar to be unsecured after the contents of the receptacle have been used up, all for the purpose of recycling. Moreover, the ""810 patent""s inherent description of restricting any rotation of the collar as it is being fitted over the ferrule provides for less than satisfactory results. That is, and as further discussed below, the severe angle of the ribs in this prior art patent prevents rotation of the collar as it is being fitted on the ferrule, resulting in more of a xe2x80x9csnowplowxe2x80x9d type deformation of the plastic ferrule, and a less than satisfactory xe2x80x9coff to onxe2x80x9d ratio for the collar.
Accordingly, it is desirable to provide an improved dispensing assembly that further advances the state of the art. In particular the present invention seeks to reduce the required application force so as to avoid collar crazing while simultaneously providing for (a) sufficient gasket compression without extrusion, (b) a desirable amount of required removal force, and (c) an increase in the ratio of axial collar removal force to application force. The present invention achieves these as well as the below mentioned objectives.
Generally speaking, in accordance with the present invention, a dispenser assembly for dispensing a substance from a receptacle is provided. In a preferred embodiment, the dispenser assembly comprises a pump assembly that comprises at least an exit tube through which the liquid leaves the pump assembly and a dip tube, coupled to the exit tube and extending into the receptacle, for transporting liquid from the receptacle towards the exit tube; a metal ferrule for maintaining a coupling of the pump assembly to the receptacle, the ferrule comprising an outer surface and an interior cavity, an aperture through which at least the exit tube of the pump assembly extends, and a plurality of bendable and depending legs for engaging the rim of the receptacle; a gasket, positioned in the interior cavity of the ferrule and having an opening through which the pumping assembly is positioned, the gasket for maintaining an airtight seal between the pumping assembly and the receptacle; and an annular collar, the collar having an inner surface and an outer surface, the inner surface comprising outwardly (when viewed from the inner surface, not from the longitudinal axis of the collar) projecting elongated ribs, the ribs extending along the inner surface thereof and non-orthogonally to a longitudinal axis of the collar; wherein the ribs are angled along the inner surface of the collar so that the collar is caused or otherwise allowed to rotate along the outer surface of the ferrule as the collar is pressed towards the receptacle and the elongated ribs form complementary elongated grooves in the outer surface of the ferrule as the collar is being fitted thereon; wherein the plurality of depending legs are locked in engagement with the rim of the receptacle to maintain the coupling of the ferrule with the receptacle; whereby an airtight seal is provided between the dispensing assembly and the receptacle when the collar is positioned over the ferrule and the collar secures the engagement of the legs with the rim of the receptacle.
A method of assembling such a dispenser assembly upon a receptacle is also provided and comprises the steps of providing a collar such as that disclosed above and pushing the collar towards the receptacle and causing it to rotate over the outer surface of the ferrule as it is forced towards the receptacle, such that the elongated ribs form complementary elongated grooves in the outer surface of the ferrule as the collar is being fitted thereon; trapping the plurality of depending legs under the rim of the receptacle, thereby maintaining the coupling of the ferrule with the receptacle; whereby an airtight seal is provided between the dispensing assembly and the receptacle when the collar is positioned over the ferrule and the collar secures the engagement of the legs with the rim of the receptacle.
Accordingly, it is an objective of the present invention to provide an improved dispensing assembly that maximizes the xe2x80x9coff-to-onxe2x80x9d ratio of application and removal forces of the collar for a given application.
Another objective of the present invention is to provide an improved dispensing assembly that reduces the likelihood that the collar will be accidentally or inadvertently pulled off the ferrule by a user, while also reducing the likelihood of damaging the outer surface thereof during the assembly thereof.
Yet another objective of the present invention is to provide an improved dispensing assembly that effectively compresses the gasket sufficiently to assure a good seal to the bottle neck and avoid leaking while reducing the likelihood of bottle breaking or collapsing.
Still another objective of the present invention is to provide an improved method of assembling such a dispensing assembly that achieves the aforementioned and below mentioned objectives.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The invention accordingly comprises the features of construction, combination of elements and arrangement of parts and sequence of steps that will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.